1. Field of the Invention
This invention relates to a photographic camera with automatic exposure control, more particularly to a camera with automatic exposure control wherein either the diaphragm aperture or the shutter speed is preset while the other is automatically set thereafter so that appropriate exposure can obtained automatically.
2. Description of the Prior Art
There are known two types of automatic exposure control in a camera, i.e., the shutter speed presetting type in which the shutter speed setting is preselected and the diaphragm aperture is automatically set thereafter, and the diaphragm aperture presetting type in which the diaphragm aperture setting is preselected and the shutter speed is automatically obtained thereafter. According to the former type of camera in which the diaphragm aperture is automatically determined, the shutter speed setting can be preselected taking into consideration the movement of the object to be photographed. It is, however, impossible with such a camera to adjust the diaphragm aperture to obtain the desired depth of field. On the other hand, in the latter type of camera in which the shutter speed is automatically set the depth of field can be controlled but it is not possible to take into account the movement of the object to be photographed. Thus, each of the two types of cameras has its merits and demerits. It is therefore desirable for the photographer to be able to choose the type of exposure control which best meets the existing conditions of scene brightness and object behavior. In order to make this choice possible, there have been proposed a number of automatic exposure control cameras in which either the shutter speed setting or the diaphragm aperture setting can be preselected according to the circumstances in which photograph is to be taken. However, these conventional cameras have the disadvantage that they are very complicated both in circuitry and in mechanism since they are required to provide switch-over between two entirely different modes of operation, one in which the shutter speed is automatically controlled and the other in which the diaphragm aperture is automatically controlled.